US5450781A - Booster - Google Patents
Booster Download PDFInfo
- Publication number
- US5450781A US5450781A US08/200,227 US20022794A US5450781A US 5450781 A US5450781 A US 5450781A US 20022794 A US20022794 A US 20022794A US 5450781 A US5450781 A US 5450781A
- Authority
- US
- United States
- Prior art keywords
- annular groove
- valve body
- radial portion
- radial
- tubular portion
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
- B60T13/00—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems
- B60T13/10—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with fluid assistance, drive, or release
- B60T13/24—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with fluid assistance, drive, or release the fluid being gaseous
- B60T13/46—Vacuum systems
- B60T13/52—Vacuum systems indirect, i.e. vacuum booster units
- B60T13/563—Vacuum systems indirect, i.e. vacuum booster units with multiple booster units, e.g. tandem booster units
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
- B60T13/00—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems
- B60T13/10—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with fluid assistance, drive, or release
- B60T13/24—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with fluid assistance, drive, or release the fluid being gaseous
- B60T13/46—Vacuum systems
- B60T13/52—Vacuum systems indirect, i.e. vacuum booster units
- B60T13/569—Vacuum systems indirect, i.e. vacuum booster units characterised by piston details, e.g. construction, mounting of diaphragm
Definitions
- the invention relates to a booster, and more particularly, to the improvement of an inner periphery of a power piston connected to a valve body thereof.
- a booster is well known in the art which includes a valve body slidably disposed within a shell, and a power piston including an inner periphery which is connected to the valve body.
- a power piston with a forwardly extending tubular portion around its inner peripheral edge, with the forward end of the tubular portion being disposed in abutment against an end face defined by a step on the valve body for connection therewith.
- Another construction for the power piston comprises a radial portion formed around the inner peripheral edge and disposed in abutment against the end face formed by a step on the valve body from the rear side for purpose of connection therewith.
- a power piston with a tubular portion extending around the inner peripheral edge of the prior art assures a required strength by the presence of the tubular portion, but suffers from an increased axial length of the valve body as a result of the provision of the tubular portion.
- the conventional power piston with a radial portion the inner peripheral edge of which is disposed in abutment against the end face defined by a step on the valve body, it is necessary to increase the wall thickness of the power piston in order to secure a sufficient strength for the inner periphery including the radial portion.
- the increased thickness of the power piston increases its weight as well as related manufacturing cost.
- the inner periphery of the power piston comprises a radial portion which extends radially and which is disposed in abutment against an end face defined by a step on the valve body from the rear side, an annular groove formed on the outer section of the radial portion and extending axially forward, and a step formed at a boundary between the annular groove and the radial portion.
- FIG. 1 is a cross section of one embodiment of the invention
- FIG. 2 is a similar cross section of part according to the prior art which corresponds to a part shown in FIG. 1;
- FIG. 3 is a similar cross section illustrating a different prior art
- FIG. 4 is a cross section of another embodiment of the invention.
- FIG. 1 shows the internal construction of a brake booster of tandem type, including a shell 1, the interior of which is divided by a center plate 2 into a forward and a rear space, with a substantially cylindrical valve body 3 slidably extending through the axial portion of the center plate 2.
- the valve body 3 includes a portion 3a of a larger diameter and a portion 3b of a smaller diameter, and is provided with a flange 3c around its outer periphery at its foremost end.
- the inner periphery of a power piston 4 is fitted around the flange 3c, and is held in place or against withdrawal by a retainer 5.
- the outer periphery of the larger portion 3a is reduced in diameter than the diameter of the remainder thereof to define a step having an end face 3d, against which the inner peripheral edge of a rear power piston 6 is disposed in abutment from the rear side and is held in place or against withdrawal by a retainer 7.
- Front and rear diaphragms 8, 9 are applied to the back surfaces of the power pistons 4, 6, respectively, to define a constant pressure chamber A and a variable pressure chamber B across the front diaphragm 8 and a constant pressure chamber C and a variable pressure chamber D across the rear diaphragm 9.
- the constant pressure chambers A and C communicate with each other through a constant pressure passage 12 formed in the valve body 3, and also communicate with a source of negative pressure through a tubing 13 connected to the front wall of the shell 1 which introduces a negative pressure. In this manner, the negative pressure is normally introduced into the both constant pressure chambers A and C.
- the both variable pressure chambers B and D communicate with each other through a variable pressure passage 14 formed in the valve body 3.
- a valve mechanism which is well known in itself, is disposed within the valve body and is operated in response to the operation of an input shaft 16 for switching the communication or the interruption of communication between the both constant pressure chambers A, C and the both variable pressure chambers B, D.
- the inner periphery of the rear power piston 6 comprises a flat radial portion 6A which extends radially, and an annular groove 6B which is formed adjacent to, but radially outward of the radial portion 6A and bulging in the forward direction.
- the annular groove 6B comprises an axially extenting inner tubular portion 6a, a radial portion 6b which continues from the tubular portion 6a, and an axially extending outer tubular portion 6c which extends from the radial portion 6b. Beyond the outer tubular portion 6c, the radially outer portion of the rear piston extends generally radially outward in the same manner as in the prior art.
- a step 6d which is circumferentially continuous is formed at the boundary between the inner tubular portion 6a of the annular groove 6B and the radial portion 6A.
- the axial size of the inner tubular portion 6a and the radial size of the radial portion 6b which constitute the annular groove 6B are chosen to be substantially equal to the radial size of the radial portion 6A which defines the inner peripheral edge.
- the axial size of the outer tubular portion 6c which forms the annular groove 6B is chosen to be slightly longer than the radial size of the radial portion 6A.
- the inner peripheral edge is formed with a radial portion 6A while a portion located radially outward thereof is formed to bulge significantly in the forward direction.
- the radial portion 6A is disposed in abutment against the end face 3d of the step on the valve body 3 for purpose of connection therewith.
- the provision of the annular groove 6B and the step 6d allows a sufficient strength to be secured around the inner periphery of the rear power piston 6 without requiring an increased wall thickness of the rear power piston 6.
- FIG. 3 shows another example of the prior art in which a stepped tubular portion 6A' is formed around the inner peripheral edge of the rear power piston 6, and the front end of the tubular portion 6A' is disposed in abutment against the bottom of an annular groove 3d' formed by a step on the valve body 3.
- the annular groove 3d' defines the rear end of the constant pressure passage 12, and accordingly it was necessary to maintain a clearance between the end face 3d of the step into which the annular groove 3d' opens and a radial portion 6a which is located radially outward of the tubular portion 6A'. This resulted in an increased axial length of the valve body 3.
- the inner peripheral edge of the radial portion 6A of the rear power piston 6 is disposed in abutment against the end face 3d defined by the step on the valve body 3, whereby a sufficient strength of the rear power piston can be secured without increasing the axial size of the valve body 3.
- the inner and outer tubular portions 6a, 6c which form the annular groove 6B are shown as exhibiting a uniform inner diameter over the entire-axial region, but an outer tubular portion 106c may be tapered to exhibit a diameter which increases in the rearward direction, as shown in FIG. 4.
Landscapes
- Engineering & Computer Science (AREA)
- Transportation (AREA)
- Mechanical Engineering (AREA)
- Braking Systems And Boosters (AREA)
Abstract
Description
Claims (4)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP5079123A JP3024427B2 (en) | 1993-03-12 | 1993-03-12 | Booster |
JP5-079123 | 1993-03-12 |
Publications (1)
Publication Number | Publication Date |
---|---|
US5450781A true US5450781A (en) | 1995-09-19 |
Family
ID=13681164
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US08/200,227 Expired - Fee Related US5450781A (en) | 1993-03-12 | 1994-02-23 | Booster |
Country Status (4)
Country | Link |
---|---|
US (1) | US5450781A (en) |
JP (1) | JP3024427B2 (en) |
KR (1) | KR970009632B1 (en) |
GB (1) | GB2275978B (en) |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2996633B2 (en) | 1997-09-02 | 2000-01-11 | 豊栄繊維株式会社 | Seamless warp knitted fabric for clothing |
Citations (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4400942A (en) * | 1980-05-13 | 1983-08-30 | Itt Industries, Inc. | Method of connecting a master brake cylinder to a brake booster and the assembly resulting from this method |
US4409885A (en) * | 1980-05-13 | 1983-10-18 | Itt Industries, Inc. | Brake booster |
US4611526A (en) * | 1984-05-22 | 1986-09-16 | Jidosha Kiki Co., Ltd. | Reaction transmitting mechanism for brake booster |
US4664016A (en) * | 1984-02-15 | 1987-05-12 | Jidoshakiki Co., Ltd. | Supply passage for brake booster of positive pressure type |
US4718326A (en) * | 1984-08-30 | 1988-01-12 | Aisin Seiki Kabushiki Kaisha | Tandem brake booster |
US4747336A (en) * | 1986-04-18 | 1988-05-31 | Jidosha Kiki Co., Ltd. | Shell connecting structure for booster |
US4759255A (en) * | 1986-05-26 | 1988-07-26 | Jidosha Kiki Co., Ltd. | Brake booster with solenoid valves |
US4787292A (en) * | 1986-09-29 | 1988-11-29 | Jidosha Kiki Co., Ltd. | Brake booster |
US4862787A (en) * | 1987-01-28 | 1989-09-05 | Jidosha Kiki Co., Ltd. | Reaction mechanism for brake booster |
US4881452A (en) * | 1987-09-03 | 1989-11-21 | General Motors Corporation | Tandem vacuum booster and diaphragm for same |
US4995302A (en) * | 1988-09-21 | 1991-02-26 | Jidosha Kiki Co., Ltd | Negative pressure booster equipment |
US5083495A (en) * | 1989-04-11 | 1992-01-28 | Jidosha Kiki Co., Ltd. | Brake booster with one-way valve on centerplate |
EP0480782A1 (en) * | 1990-10-10 | 1992-04-15 | Alliedsignal Europe Services Techniques | Tandem arranged vacuum operated brake booster |
US5121673A (en) * | 1989-08-31 | 1992-06-16 | Jidosha Kiki Co., Ltd. | Apparatus for preventing percussion beats in brake booster |
US5228377A (en) * | 1991-07-19 | 1993-07-20 | Jidosha Kiki Co., Ltd. | Brake booster |
US5287793A (en) * | 1992-04-09 | 1994-02-22 | Jidosha Kiki Co., Ltd. | Power piston assembly for booster with diaphragm retainer |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5992243A (en) * | 1982-11-17 | 1984-05-28 | Jidosha Kiki Co Ltd | Booster for braking force |
US4671167A (en) * | 1984-03-19 | 1987-06-09 | Tokico Ltd. | Pneumatic booster |
JPS649871U (en) * | 1987-07-08 | 1989-01-19 |
-
1993
- 1993-03-12 JP JP5079123A patent/JP3024427B2/en not_active Expired - Fee Related
-
1994
- 1994-02-23 US US08/200,227 patent/US5450781A/en not_active Expired - Fee Related
- 1994-02-23 GB GB9403438A patent/GB2275978B/en not_active Expired - Fee Related
- 1994-03-04 KR KR1019940004225A patent/KR970009632B1/en not_active IP Right Cessation
Patent Citations (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4400942A (en) * | 1980-05-13 | 1983-08-30 | Itt Industries, Inc. | Method of connecting a master brake cylinder to a brake booster and the assembly resulting from this method |
US4409885A (en) * | 1980-05-13 | 1983-10-18 | Itt Industries, Inc. | Brake booster |
US4664016A (en) * | 1984-02-15 | 1987-05-12 | Jidoshakiki Co., Ltd. | Supply passage for brake booster of positive pressure type |
US4611526A (en) * | 1984-05-22 | 1986-09-16 | Jidosha Kiki Co., Ltd. | Reaction transmitting mechanism for brake booster |
US4718326A (en) * | 1984-08-30 | 1988-01-12 | Aisin Seiki Kabushiki Kaisha | Tandem brake booster |
US4747336A (en) * | 1986-04-18 | 1988-05-31 | Jidosha Kiki Co., Ltd. | Shell connecting structure for booster |
US4759255A (en) * | 1986-05-26 | 1988-07-26 | Jidosha Kiki Co., Ltd. | Brake booster with solenoid valves |
US4787292A (en) * | 1986-09-29 | 1988-11-29 | Jidosha Kiki Co., Ltd. | Brake booster |
US4862787A (en) * | 1987-01-28 | 1989-09-05 | Jidosha Kiki Co., Ltd. | Reaction mechanism for brake booster |
US4881452A (en) * | 1987-09-03 | 1989-11-21 | General Motors Corporation | Tandem vacuum booster and diaphragm for same |
US4995302A (en) * | 1988-09-21 | 1991-02-26 | Jidosha Kiki Co., Ltd | Negative pressure booster equipment |
US5083495A (en) * | 1989-04-11 | 1992-01-28 | Jidosha Kiki Co., Ltd. | Brake booster with one-way valve on centerplate |
US5121673A (en) * | 1989-08-31 | 1992-06-16 | Jidosha Kiki Co., Ltd. | Apparatus for preventing percussion beats in brake booster |
EP0480782A1 (en) * | 1990-10-10 | 1992-04-15 | Alliedsignal Europe Services Techniques | Tandem arranged vacuum operated brake booster |
US5228377A (en) * | 1991-07-19 | 1993-07-20 | Jidosha Kiki Co., Ltd. | Brake booster |
US5287793A (en) * | 1992-04-09 | 1994-02-22 | Jidosha Kiki Co., Ltd. | Power piston assembly for booster with diaphragm retainer |
Also Published As
Publication number | Publication date |
---|---|
GB9403438D0 (en) | 1994-04-13 |
GB2275978B (en) | 1996-06-12 |
JPH06263025A (en) | 1994-09-20 |
JP3024427B2 (en) | 2000-03-21 |
KR970009632B1 (en) | 1997-06-17 |
GB2275978A (en) | 1994-09-14 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US5337650A (en) | Booster for brake or clutch | |
US5228377A (en) | Brake booster | |
US5062348A (en) | Seal unit for brake booster | |
US4516474A (en) | Tandem diaphragm brake booster | |
US5651300A (en) | Booster | |
US5450781A (en) | Booster | |
US5943937A (en) | Pressure differential operated brake booster | |
US5083495A (en) | Brake booster with one-way valve on centerplate | |
US6334384B1 (en) | Brake booster | |
US4984507A (en) | Three chamber brake booster with variable pressure passages having a minimum channel length | |
US4881452A (en) | Tandem vacuum booster and diaphragm for same | |
US5170628A (en) | Brake booster | |
US6578360B2 (en) | Master cylinder | |
US4976188A (en) | Brake booster | |
US5063830A (en) | Brake booster | |
US5697284A (en) | Booster | |
EP0573234B1 (en) | Improvements in pneumatically-operated boosters for vehicle braking systems | |
US5823089A (en) | Booster | |
US5083496A (en) | Seal unit for brake booster | |
US5287793A (en) | Power piston assembly for booster with diaphragm retainer | |
US4807521A (en) | Actuator casing | |
US5386760A (en) | Brake booster with reaction disk retainer | |
US5704455A (en) | Automatic brake booster | |
US5158006A (en) | Brake booster | |
JPH08198095A (en) | Brake booster |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: JIDOSHA KIKI CO., LTD., JAPAN Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:HIRASHITA, HIROSHI;REEL/FRAME:006896/0968 Effective date: 19940120 |
|
FEPP | Fee payment procedure |
Free format text: PAYOR NUMBER ASSIGNED (ORIGINAL EVENT CODE: ASPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY |
|
CC | Certificate of correction | ||
FPAY | Fee payment |
Year of fee payment: 4 |
|
AS | Assignment |
Owner name: BOSCH BRAKING SYSTEMS CO., LTD., JAPAN Free format text: CHANGE OF NAME;ASSIGNOR:JIDOSHA KIKI CO., LTD.;REEL/FRAME:011379/0706 Effective date: 20001030 |
|
FPAY | Fee payment |
Year of fee payment: 8 |
|
AS | Assignment |
Owner name: BOSCH AUTOMOTIVE SYSTEMS CORPORATION, JAPAN Free format text: CHANGE OF NAME;ASSIGNOR:BOSCH BRAKING SYSTEMS CO., LTD.;REEL/FRAME:014913/0827 Effective date: 20031205 |
|
REMI | Maintenance fee reminder mailed | ||
LAPS | Lapse for failure to pay maintenance fees | ||
LAPS | Lapse for failure to pay maintenance fees |
Free format text: PATENT EXPIRED FOR FAILURE TO PAY MAINTENANCE FEES (ORIGINAL EVENT CODE: EXP.); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY |
|
STCH | Information on status: patent discontinuation |
Free format text: PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362 |
|
FP | Lapsed due to failure to pay maintenance fee |
Effective date: 20070919 |